gitproto: match CommandStatusErr by value so target-ref moves classify

[nodo]

Problem

ErrTargetRefMoved (PR #71, unreleased) never attaches on the real push path. asRefRejectedError and annotateLeaseFailure match go-git's CommandStatusErr with a pointer target:

var cs *packp.CommandStatusErr
if !errors.As(err, &cs) { return err }

but go-git returns CommandStatusErr by value from ReportStatus.Error() (value receiver Error(), constructed by value in report_status.go). errors.As against a **CommandStatusErr target never matches a value-typed CommandStatusErr in the chain, so:

• asRefRejectedError falls through → no *RefRejectedError, moved never set → errors.Is(err, ErrTargetRefMoved) is always false on a live receive-pack rejection.
• annotateLeaseFailure falls through → the lease-failure hint never fires.

Net effect: every concurrent target-ref rejection (remote ref has changed) passes through unclassified. The downstream mirror-pipeline worker that relies on errors.Is(err, ErrTargetRefMoved) to classify benign races sees nothing — the typed-rejection feature is inert in production.

The existing tests masked this by feeding &packp.CommandStatusErr{} (a pointer) as input, which the pointer target does match — but that is not how go-git hands the error over.

Fix

• Both functions now use a value errors.As target (var cs packp.CommandStatusErr), matching go-git's actual return type. go-git's own tests confirm a value target is correct (s.ErrorAs(rs.Error(), &CommandStatusErr{})).
• The table tests now build their input via go-git's real (&packp.CommandStatus{...}).Error() (value), and the underlying-error assertions use value targets.
• New TestAsRefRejectedError_RealReportStatusPath drives a real ReportStatus.Error() end to end through the production wrap — it fails on the pointer target and passes on the value target, so a pointer-vs-value relapse fails CI.

Verification

go test ./..., go vet, gofmt all clean. Confirmed the new test fails on the pre-fix pointer target and passes after.

Bug was in the unreleased typed-rejection feature (#71); never shipped in a tagged release.

🤖 Generated with Claude Code

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Note

Low Risk
Narrow error-wrapping fix in push status handling with stronger tests; behavior change is enabling the intended unreleased API rather than altering unrelated push logic.

Overview
Fixes typed push-rejection handling on the live receive-pack path so errors.As into *RefRejectedError and errors.Is for ErrTargetRefMoved actually work.

annotateLeaseFailure and asRefRejectedError now use a value packp.CommandStatusErr in errors.As, matching go-git’s value-typed ReportStatus.Error() output; the previous pointer target never matched, so lease hints and concurrent-move classification were effectively no-ops in production.

Tests build inputs via CommandStatus.Error() (not hand-built pointers), assert unwrap with value CommandStatusErr, and add TestAsRefRejectedError_RealReportStatusPath to guard against pointer-vs-value regressions. CHANGELOG documents the fix and clarifies that embedders should use a value errors.As target for the underlying go-git error.

^{Reviewed by Cursor Bugbot for commit 84f71be. Configure here.}

[nodo]

Superseded by #73 — same fix, recreated with the Entire session checkpoint trailer attached.